Autocollimating button



ing material provided in the recess and 0 closing saidrecess.

V I In the copending "Patented Jan. 29, 1946 UNITED STATES PATENT OFFICE AUTOCOLLIMATING BUTTON I Neil Broderson, Rochester, N. Y., assignor to the Government of the United States of America, as represented by the Secretary of War . Application February 5, 1944, Serial No. 521,292

e i '7 Claims. invention relates to buttons andmore particularly it is; directed to a method of making autocollimating buttons adapted to translate invisible light into visible light.

j One of the objects of the invention is to pro wide a method of protecting lacquer between two .weldedpieces of plastic.

Another object of thelinvention is to provide .a methodof making buttons in which material to be guarded is placed between dual members \rotatable incontact with each other whereby frlction is set up between the members with the productiomof heat causing the melting ofcontactingportions ofjthemembers thus effecting the cementing of the dual members.

Another object of the invention is to provide fa method ofmaking autocollimating buttons in which light generating material is placed between dual lens components frictionally welded tosether.

1 {Another object of the invention is to provide an autocollimating button in which dual memhers are welded together by frictional contact with .each other and having a recess in one of the members, with phosphor or other light generata guard of the properties'which the autocollimatmy shield at the focal point of a parabolic rehector, which shield has-associated therewith, or may have integral'the'rewith, a phosphor back U which faces ,the parabolic reflector. Hence, none butlight reflectedfrom the back is returned by jthe button."

k I e application SerialNo. 474,761, filed Februaryd, 1943, two plastic members are welded together bybeing mounted in chucks in 1 opposed relation to each other, with one of the fichucks, b'ein'g revolved. at high speed, while the lother chuck is maintained in a freely mounted j position andflca'p'able of revolving. A surface of .xthe. plastic member mounted on the chuck revolving at high speed isbrought into contact with the above-mentioned application for use in the manufacture of autocollimating buttons, particularly autocollimating buttons adapted to change invisible light into visible light. In such construction, light generating material is employed, which if placed at the focal point in the button becomes visible on being energized by the application of either invisible or visible light thereto. It has been found that the invention described in the copending application could suitably be applied to the manufacture of such buttons, but for the fact that the welded friction zone between the two members is in general coincidence with the point of application of the light generating material. This coincidence is understood in that violence in the friction contact of the two members tends to disperse the light generating material and in fact tends to remove it completely from the surface to which it is applied.

It is, accordingly, another object of the invention to provide an autocollimating button which may be made in two parts and may be cemented together by, means of the friction method without loss of light generaitng material applied prior to the cementing of the two parts of the button.

Obviously, the invention is not limited to the guarding of light generating material in plastic buttons but is more broadly applicable to the general art of guarding materials situated between two surfaces which are to be welded together, especially by friction. Other applications of the invention will be readily understood by those familiar with the art.

With the above and other objects and advantages in view, the invention consists of certain features of construction and operation of parts which will hereinafter be described and shown in the accompanying drawing in which:

Figure 1 is a top plan view of a machine having two chucks rotatably mounted thereon, with dual parts of the improved button to be frictionally welded together carried by the chucks;

Figure 2 is an enlarged vertical sectional view of the dual lens elements of an autocollimating button with a recess containing light generating material in one of the parts of the button and a guard for sealing the light generating material in the recess prior to welding the dual lens elements of the button together; and

"of -=button portion l l.

thereon. The driven shaft 2 has a chuck 4 mounted on its inner end and a pulley 6 mounted on its outer end, which pulley 6 is driven at a suitable constant speed for rotating the driven shaft 2 by a motor 1 through a belt 8. The chuck 4 on the inner end of shaft 2 holds a portion or lens element 9 of 'the improved; button indishaft 2 and holds a portion orilens element ll of the button. The sleeve I2 is slidably mounted on the revoluble shaft 3 and-is actuated thereon by means of a pivoted lever 13 for moving the portion ll of the button into and out of frictional contact with therevolving. portion 9 of the button.

-The button. portions .or .lens elements Sgand H held in the chucks 4- andj5, respectively,. are more particularly.illustrated in Figure .2. "The upper driven button portion 9 includes an autocollimating optical outer surface 14 and an inner surface 15 to .be weldedtothe innersurface'lfi The inner surface 15 of button-portion9 isslightlyconvexed to compensate for differential velocity: in the welding process as the outer part .of the convexed surface I5 away fromthe center .of rotation moves considerably faster than the part. near the center. .A recess-or socket His centrally formed in -the flat surface 1l6 of the undriven bottom portion ll, with the.innersurface or bottom v1.8 of the recess 11 being curved .andcovered with phosphor or other light generatingmater-ial 1 9 and .a member in "the form of. a plug .or insert 29, preferably -:made of opaque plastic material, isLfitted into the 180855 .-I I.

The plugs-Ml. conforms -.to. the same shape and size-as the recess .l'landisprov'ided witha curvedsurface 2| provided .withfblack lacquer '22 which is protectedthesameasthe light generating material.l9.as..both..are..'between .thezplug 20: and the bottom button portion orlens ..element 1 I.

This. black lacquer. .22. on plug. 20 serves .as a direct. light. ray. v shieldLshutting off from afront viewthe light generating material 19.

In forming the improved. autocollimating. buttonA; Figures 2;and 3, after thelight generating material H! has been placed in .thebottom 18 of the recess I! on the :bottom .buttonmember --II and the plug 20.:hasbeen fittedintorecess -I I, the button member H is mounted on the chuck :Sand the-upper button .member 9 ismounted on the chuck 4 with thesurfaces l5- and 16 f -members 9 and l I, respectively, being in opposed relationto each other. Upon startingthe motor 1, the driven shaft 2 is rotated at-any suitable constant high speed through the belt 8zand pulley 6, thereby'rotating.chuckd holding the button portion 9. Thelever lv3.is.then,operated by=the ,handlto-move the sleeve .l 2 inwardly wherebythe inner surface 16 of thenon-driven button-member .-.l I- inechucki is caused to engage the..inner ..surface 15 of buttQn'member-Qthus settingup friction between surfaces lsand. .l ,6,:.with the production of heat .and'vcausing the melting of .the plastic. material surfaces and 1.6, thus-effecting the cementing or welding-of the'button members 9 and I I together.

The'plug 29 prevents the light generating material :19 in the recess .I! from spreadingall over the surface I6 of button portion II or losing all of the light generating material upon surface ii of button portion 9 rotating at a high speed being brought into contact with surface l6 of non-rotating button portion ll. As the plug member 20 fits exactly into the recess I1, it will be held temporarily therein by friction of its surface against the surface of the buttonmember ll surrounding the recess. On the welding of the dual button portions or members 9 and II in the man- :ner described above by the friction of the dual button portions meeting each other, the surface lion button member 9 will not onl be welded .to the surface I6 of button portion II, but also welded-tothe outer fiat surface 23 of plug 20 -which1fits into recess II.

The autocollimating buttons contemplated by this invention are susceptible of a number of uses. For example',markers for roads or paths through mined combat areas. The particular advantage is that a phosphorescent or fluorescent light generating material-may belocated at 'the'focal point 'tion'by occupants of aircraft and other persons not in the "line of the 'concentrated'beam.

It will "thus be .seenthat there'is herein'provided a useful and efficient form of button'parti'cularly of the autocollimating type adapted to translate invisible'light into visible light. -Even thoughthere has herein -beenshownand'described certain features of construction and operation of parts, it is. neverthelessto be understood'that various changes may be made therein, if the -changes do not depart from the spirit "or scope of the claims.

Having .thus described .m invention; what I claim as new and wish to-secure 'by,LettersPat- 1. .Amethod of. making auto'col'limatingfbuttto'nsof' dual members; whichconsi'sts of forming arec'essiin one'of said'members; placing light.gen-

erating material in said recess,. sealing the light .generatingmaterialin said recess 'andfrictionally engaging said members to produce heat'for melt- 'ing contacting surfaces of said members and ef- 'fecting a'welding thereof.

'2. A; method of .making 'autocollimating buttons of dual members, which consists of forming arecess in one .of said members, placing light gencrating 'material'in said recess, fitting a sealing .member provided with a light shield in said rea black. lacqueredmember provided in said socket.

4. .An. autocollimating button 'comprisingbonded dua'.l.members,-a recessformed in one of said members, Ilight. generating material providedgin .said. recess, a plug fitted .into said. recessifor guarding said light generating material andlig'ht shielding material. provided: .on said, plug.

5. .An autocollimating button comprising dual members secured togethenarecess formed in .one

- of saidmembers, a lightgenerating. material p0 sitioned in said recess, an opaque member mounted in said recess and light shielding material provided on said opaque member.

6. An autocollimating button comprising a pair of-lens members provided with opposed contacting surfaces and bonded along said contacting 5 surfaces, one of said lens members being provided with an outer collimating surface, the contacting surface of one of said lens members being provided with a recess, a light generating material jacent said light generating material for forming a light shield between said material and said collimating surface.

7. A method of making. autocollimating buttons of dual members, which consists of forming a recess in a face of one of said members, placing a light-generating material in said recess, sealing the light generating material in said recess and bonding the sealed recessed face of said positioned in said recess, and a sealing member 10 member to the remaining member.

positioned in said recess, said sealing member being provided with a light absorbing surface ad- NEIL O. BRODERSON. 

